SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ce4141744b6428da06bb8431a69341408ecccb4775adc0c8834724fc756d949' 
  AND token = 'LXGclHsOQYzwTrY4Ext/dJ7CzpVEjDi9Vq6oKuh27dg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables